Category Plants & Animals

               The study of the fossils has revealed that hundreds of species of animals and plants have come and gone since the creation of earth. To begin with, these species became extinct as a result of natural causes. The animals and plants that disappeared were those that were unable to adapt fast enough to the changing conditions of the earth or were unable to compete with their rivals for the available food supplies. However, there are other instances, such as the case of dinosaurs, in which the reason of their extinction is still not very clear. The animals which became extinct millions of years ago were never seen by man. Also there are some others that were alive only a few hundred years ago and man himself has been responsible for killing them and causing their extinction. Do you know which animals became extinct during the last few hundred years? 

                   There was a bird called dodo which became extinct by the end of 17th century. This bird lived on the small island of Mauritius in the Indian Ocean and had no proper wings to fly. For this reason people called them dodos which means ‘simpleton’ or ‘stupid’. It was hunted down by the Dutch sailors who landed in the island in 17th century. Dodo meat was good to eat and hence carried away in ships by the Dutch. Dogs and rats started eating dodo eggs and chicks. As a result all dodos vanished by the middle of 17th century. The same story marked the extinction of another bird called the Great Auk. This penguin-like bird lived on the islands north of Scotland as recently as the mid-19th century. Egg collectors and hunters drove it to extinction by 1844. 

Continue reading “Which animals are extinct now?”

               There is a family of mammals called ‘sloth’ found in tropical South America, the members of which spend most of their lives in upside down position. They move about the tree tops in very slow motion usually at night. They use the hooked claws of both their toes and fingers to move upside down and spend most of their lives in this peculiar position. The sloths can even go to sleep in this position. In sleep, their muscles become fixed and would not relax until the animal wakens and purposely does so. The sloths eat, mate and even give birth to their young in this position.

               There are two interesting characteristics related to this strange habit of sloths. The first is its ability to turn its head almost right round to compensate for its reverse position. The second relates to its hair that lies in the opposite direction to that of most of the other animals. The sloth’s hair runs from its belly round to its back, and this ensures that heavy tropical showers run straight off.

               The sloth hardly has any tail. Its nose is blunt and the peglike teeth are well-developed. The animal is hardly visible in trees because green algae cover the animal’s hair, providing camouflage. It feeds on leaves, buds and fresh twigs of trees.

               There are two main species of sloths. The unau or two-toed sloth which has two toes on the front and the ai, or three-toed sloth which has three toes on the front feet. In prehistoric times there were huge giant sloths that were about 6 metres (20 ft.) tall.

               Just as lion is called the king of beasts, the same way shark can be called the   king of fishes. It is the fastest and the most dangerous fish in the sea. It is also the largest of all fishes, ranging from one foot to over 50 feet in size. Another reason for calling it the king is that it belongs to one of the oldest groups of creatures alive in the world today. Some fossils of sharks are believed to be around 250,000,000 years old.

               A shark is a saltwater fish that belongs to the class Chondrichthyes. Its skeleton is made up of cartilage rather than bones. Its skin is covered with many small scales which are like sandpaper. There are about 400 species of sharks in the world. The dog-fish shark grows up to around 3 ft. in length. It feeds on small fish and invertebrates. The whale shark, the largest of all fish, can reach about 50 feet in length. It is the least dangerous. These sharks have many razor-sharp teeth. The great white shark, the greediest monster, swallows its prey whole. The remains of big animals, such as seals, dolphins and smaller sharks have been found in its stomach.

               A shark will eat almost anything found in the sea from the tiniest sort of sea creatures to other sharks, turtles, seals or dolphins. They have been known to swim up rivers and attack crocodiles, horses and elephants which might have waded into the water. They are also found to attack people swimming in the sea. When in pursuit of their prey, they can move very fast. They follow the ships to feed on the waste food thrown overboard from the kitchens of the ships. Some sharks live and hunt alone, while others prefer to roam the seas in packs. Most of the sea beaches in Australia and South Africa are protected from sharks by iron-nets and electric barriers, for the safety of the swimmers.

               Sharks are caught in large number every year. Their meat is very nutritious and cheap, and can be quite delicious if properly cooked. Their skin is used for binding books and covering boxes, and for making bags and shoes.

               The most beautiful shark is the mako shark. It is snow white underneath and brilliant blue on the top. It is very fast and ferocious and a strong fighter when caught alive.

The birds which feed on other animals are called the birds of prey. They catch and feed on animals that are usually smaller than themselves. They may catch their prey anywhere on the ground, in air or in water. Not all birds bother to choose their prey. Some even feed on the flesh of dead animals. Do you know which the birds of prey are?

Among the common birds of prey are: buzzards, eagles, falcons, harriers, hawks, kestrels, vultures and wood peckers. Owls also catch smaller animals and feed on them but they are put in a different category. Most of the birds of prey are brown-coloured. They are found on all the continents except Antarctica. They kill their prey with their strong sharp talons, and pluck and tear the flesh with their narrow, hooked beaks. These birds normally swallow huge chunks of food and regurgitate the pellets of indigestible matter.

The birds of prey attack in two ways. Kestrel hunts by hovering over open ground, and then plunging down on its prey before it can escape. Falcon stoops or dives its head first at its prey and catches it in its talons. Eagles are powerful and soaring birds.

Some eagles hide in a tree and wait for their prey to wander into a clearing. Carrion eaters soar on outstretched wings at considerable heights for hours together and peering down for animals already dead or one about to die. In contrast to it the small birds of prey like the sparrow hawk dash at high speed through trees to spring surprise on a small creature. The birds of prey also kill with their feet. Although some use the beak for the purpose, yet the sharp, curved talons of the feet are the main killing weapons. The rear and inner talons are usually larger than the middle or outer one. These help the bird to exert a strong pincer grip on the prey.

The birds of prey hunt a variety of animals such as rabbits, hares, grouses, fishes and many other birds. 

          It may be surprising to note that fishes can smell things just like other creatures. And like other animals they have noses for this purpose.

          There are two pairs of nostrils in a fish. Each nostril has two openings which are called pits. One opening is in the front, and the other directly behind it. The two are separated by a small flap. However, the location of the nostrils may vary from species to species. 

          When a fish is under water, a current of water enters from the front pit and comes out through the rear one. As the water flows inside, it stimulates the sense cells which enable the fish to catch the smell. Many fishes have a keen sense of smell. They can detect even the faintest smells.

          In fact, the sense of smell may be important to a fish in helping it find its way home. Some fish could distinguish between the water of two creeks through smell. But if their noses are plugged, they get lost. To prove this fact some researchers had performed certain experiments. In one experiment a large number of salmon fish were taken out of their home stream. Half of them had their noses plugged; the other half did not. The fishes with plugged noses got lost and the rest half could find their way back home again. Anglers use peculiar scented fish-food to attract them.

          Apart from the sense of smell the fishes have other sensory perceptions also such as the sense of touch, taste, hearing and seeing.